This type of water dispenser is configured such that when water stored in a cold water tank which is capable of cooling water therein runs short, water is automatically supplied into the tank through a water supply line, the water thus supplied is cooled by a heat exchanger mounted to the cold water tank, and cold water in the cold water tank can be discharged into the atmosphere through a cold water discharge line when a user operates a lever or a cock to open a valve. The closer water in the tank is to the bottom of the tank, the colder it is. If the water dispenser is configured such that water introduced into the cold water tank can directly flow down to the bottom of the tank, the not-yet-sufficiently-cooled water is quickly mixed with the well cooled water at the bottom of the tank, warming the water at the bottom of the tank. In order to prevent this, a baffle is usually provided in the cold water tank which interferes with the downward flow of water (see, e.g., JP Patent Publication 2010-52752A (especially FIG. 1), JP Patent Publication 2011-102154A (especially FIG. 1), and JP Patent Publication 2003-12092A (especially FIGS. 1 and 2)).
With this arrangement, a low-temperature water layer which is lower in temperature than water above the baffle is generated in the lower portion of the cold water tank which is within the height range from the bottom of the cold water tank to the outermost circumferential portion of the baffle, from the bottom of the tank. The cold water discharge line is arranged to discharge water forming the low-temperature water layer. If the outermost circumferential portion of the baffle is fitted to the inner wall of the cold water tank or by minimizing the horizontal gap therebetween, it is possible to increase the area of the baffle, which divides the interior of the cold water tank into upper and lower portions, thereby increasing the effect of interfering with the downward flow of water. But in this case, water above the baffle cannot sufficiently smoothly flow through the baffle into the lower portion of the cold water tank. To avoid this problem, the baffle may be formed with water transfer passages at its portion located inwardly of the outermost circumferential portion so that water introduced into the portion of the cold water tank from the water supply line can be fed into the lower portion of the cold water tank through the water transfer passages.
The water transfer passages have a terminal end opening which faces vertically downwardly, just like the gap defined between the inner wall of the cold water tank and the outermost circumferential portion of the baffle. Thus water is discharged through the terminal end openings substantially downwardly into the lower portion of the cold water tank. But since it is possible to reduce the momentum of water flowing through the water transfer passages by reducing the sectional areas of the leading end openings of the water transfer passages, it has not been considered a problem to discharge water downwardly from the terminal end openings of the water transfer passages.
However, if the gap between the inner wall of the cold water tank and the outermost circumferential portion of the baffle is eliminated or reduced to a minimum, while ensuring a sufficient flow rate of water through the baffle with a smaller number of water transfer passages, in order to mount the baffle more simply or to simplify the shape of the baffle, it is necessary to increase the sectional area of the respective water transfer passages over the entire length thereof. This increases the momentum of water when discharged downwardly into the lower portion of the cold water tank from the terminal end openings of the water transfer passages. Water discharged from the water transfer passages can thus be more easily mixed into the low-temperature water layer.